I think this sets a scary precedent. Kudos to a DA that would charge the man if nothing malicious was being done with the connection. He'd probably have done the same if someone was caught getting a drink out of an the homeowner's garden hose in the front yard. Theft of water service, right?
No doubt it's inevitable that these sorts of stories will become more commonplace.
A few comments here though:
1. Regardless of the WiFi angle, seeing somebody hanging around your property for an extended period of time and acting suspicious is likely to raise a few hairs.... nothing new there. Regardless of what the guy was doing, the police would likely be interested in speaking to him about it.
2. I can see many parallels between WiFi issues and past hot items such as Satellite TV, Cell phone monitoring, EMS monitoring and even Speed Radar detection. One of the old arguments about signals being "freely available" (ie. not encrypted) has pretty well been shot down in most cases as a legal defense... in effect the right to freely use unencrypted signals around us has been removed.
3. Cell phone companies hate WiFi, for obvious reasons. Look for more pressure to be placed on governments by the big cell companies to make it illegal to use "unsolicted" WiFi connections (might already be illegal, but it's fuzzy right now). At the same time they'll want clarification about who can do what with WiFi ie: coverage range of private WiFi setups etc. We've seen some Cell companies get involved with HotSpots in various locations, I would expect that trend to continue at an increased rate.
Okay, I'm starting to get cynical here, but I think the writing is on the wall... the days of free wifi as it exists now are likely numbered.
Unfortunately, the trend in our society is to regulate and control. If there are no more additional regulations then the people who make those regulations (or set up barriers) cannot justify their existance.
I see a parallel in free internet access at libraries. When I first started chasing, I could wander into any university library and many local libraries and get on the internet. Now, most universities require log on codes and local libraries have sign up sheets. I expect that more people will encrypt their wi-fi and hotels will require a sign on codes. Enjoy it now.
No lawyer here, but it seems to be a similar issue to the pretty well-developed law of Trespass. It's going to end up revolving around whether someone is "knowingly" usurping a connection, whether a reasonable person can assume that a particular connection is in the public domain, and whether the use is incidental or wanton. Either that or we become a police state.
The other aspect is that it's not clear who's potentially committing the crime. If I allow my neighbor to run a cable onto my property and tap a connection it's mainly the owner of the connection that's afoul of the current laws. Wifi is even murkier -- more like setting up a big tv visible from the neighbor's house or the street. Anyone in view with a universal remote bought at Wal-Mart can then watch whatever they want.
Some are old enough to remember the days when AT&T had a monopoly on phone service. It was against the law (felony, I think!) to hook up additional devices, e.g. answering machines or extensions, in your home without reporting them to Ma Bell and paying an extra fee. I remember my dad, MHRIP, conspiratorially wiring extensions and instructing the family what to do if the Phone Company called or paid a visit. Technically, you see, the additional devices had a non-zero "ringer equivalent" and thus "used" some additional Phone Company resources.
IMO, there's probably more to the St. Petersburg case then was reported so far that lends itself to prosecution.
In almost all cases chaser use of a wifi connection is incidental and far under any possible Federal radar. They're also generally business or public connections, rather than residential, and the law of Trespass works differently for them. For example, if I walk into a Burger King, set up my tripod and start to take pictures, the manager can tell me to stop or leave. If I don't, then it's Trespass. On the other hand, if I walk onto the patio of a stranger's house and do the very same thing, it's Trespass then-and-there because I didn't have any business to be there, and a reasonable person knows that.
I suspect that he may have been downloading something more incriminating than RUC model data. The clue is that the story refers to the wireless connection owner seeing the glowing computer screen, going out to see the guy, and having him snap the screen shut ... repeatedly. The guy was apparently concerned more with what was visible on the screen than how he got it.